diff options
| -rw-r--r-- | beef.c | 100 | ||||
| -rw-r--r-- | readme.md | 11 | ||||
| -rw-r--r-- | test.bf | 20 |
3 files changed, 131 insertions, 0 deletions
@@ -0,0 +1,100 @@ +#include <stdlib.h> +#include <stdio.h> +#define SIZE 1024 + +struct stack { + long int data; + struct stack *next; +}; + +void push(struct stack **s, long int i) { + struct stack *nuevo = malloc(sizeof(struct stack)); + nuevo->data = i; + nuevo->next = *s; + *s = nuevo; +} + +void pop(struct stack **s) { + struct stack *temp = *s; + *s = (*s)->next; + free(temp); +} + +int main(int argc, char **argv) { + if (argc != 2) return 1; + FILE *source = fopen(argv[1], "r"); + if (!source) return 1; + struct stack *open_brackets = 0; + char tape[SIZE] = {0}; + char *curr = tape; + int lineNr = 1; + int exit = 0; + while (!feof(source) && !exit) { + char c = fgetc(source); + switch (c) { + case '\n': + lineNr++; + break; + case '+': + *curr += 1; + break; + case '-': + *curr -= 1; + break; + case '>': + if (curr != &tape[SIZE - 1]) curr++; + else curr = &tape[0]; + break; + case '<': + if (curr != &tape[0]) curr--; + else curr = &tape[SIZE - 1]; + break; + case '.': + putchar(*curr); + break; + case ',': + *curr = getchar(); + break; + case '[': + if (*curr) { + push(&open_brackets, ftell(source)); + } + else { + int counter = 1; + while (counter > 0 && !feof(source)) { + c = fgetc(source); + if (c == '[') counter++; + else if (c == ']') counter--; + } + if (feof(source)) { + printf("Error: Can't find matching ']' at line %d\n", lineNr); + exit = 1; + } + } + break; + case ']': + if (*curr && open_brackets) { + fseek(source, open_brackets->data, SEEK_SET); + } + else if (open_brackets){ + pop(&open_brackets); + } + else { + printf("Error: Can't find matching '[' at line %d\n", lineNr); + exit = 1; + } + } + } + if (open_brackets) { + lineNr = 1; + rewind(source); + while (ftell(source) != open_brackets->data) { + if (fgetc(source) == '\n') lineNr++; + } + printf("Error: Can't find matching ']' at line %d\n", lineNr); + while (open_brackets) pop(&open_brackets); + exit = 1; + } + fclose(source); + return exit; +} diff --git a/readme.md b/readme.md new file mode 100644 index 0000000..97f942e --- /dev/null +++ b/readme.md @@ -0,0 +1,11 @@ +Beef +==== + +Brainfuck interpreter +--------------------- + +Usage: beef [file] + +Brainfuck is a turing-complete minimalist esoteric language created by Urban Müller. + +More info here https://en.wikipedia.org/wiki/Brainfuck @@ -0,0 +1,20 @@ +Prints hello in an endless loop +++++ ++++ ++ +[ + [ + >++++ +++ + <- + ] + >++. + <++++ ++++ ++ + [ + >+++ + <- + ] + >-. + ++++ +++ + .. + +++. + [-] + <++++ ++++ ++. +] |